Presidential hopeful Bernard Sanders scored a narrow, upset victory Tuesday over Democratic front-runner Hillary Clinton in the Michigan primary, blunting her momentum even as she secured a lopsided win in the Mississippi contest.

Clinton will emerge with more delegates but with new doubts about her campaign's appeal to blue-collar voters as she heads into important primaries in such industrial states as Ohio, Illinois and Missouri on March 15.

Sanders predicted his campaign would be more successful in the weeks ahead.

"Frankly we believe that our strongest areas are yet to happen," the Vermont senator said. "We're going to do very very well on the West Coast."

On the Republican side, Donald Trump won both the Mississippi and Michigan primaries, making it harder for the three other GOP contenders to lay claim to the presidential nomination. Texas Sen. Ted Cruz won the Idaho caucuses Tuesday night.

"So many horrible, horrible things said about me in one week," Trump told an audience in Florida. "It shows you how brilliant the public is that they realize these were lies."

In Michigan, Sanders spent countless hours and more than $1 million for ads in recent weeks, hoping to appeal to working class voters. He focused heavily on the issue of free trade, arguing that foreign trade deals have taken manufacturing and other jobs away from American workers, especially in the Rust Belt.

Sanders spoke about his opposition to the North American Free Trade Deal in the 1990s. He also has highlighted his opposition to the Trans-Pacific Partnership. Trade is considered a hot-button issue, with Ford Motor Co. saying it opposed the trade accord in its current form in November. About 60 percent of the voters who were concerned about the trade issue voted for him, exit polls showed.

Clinton stressed her strong support for President Barack Obama and her intention continue to pursue his policies. About 63 percent of the voters who support continuing Obama's policies voted for Clinton, the polls showed.

Sanders was projected by the Associated Press to win Michigan, leading Clinton by less than 2 percentage points with 99 percent of the ballots counted. The narrow margin in the race means the candidate will split Michigan's 130 Democratic delegates.

However, Clinton still maintains a commanding lead in the delegate count needed to win the nomination.

Joe Trippi, who served as campaign manager for Democrat Howard Dean's 2004 run, said not much has changed due to the way the party apportions delegates to each candidate.

"It doesn't do you any good when your wins are by a few points," he said, contrasting it with Hillary's victories in southern states. "He has some big wins, but they have been few and far between."

Exit polls Tuesday also reflected trends common in other states: Sanders won about 80 percent of voters younger than 30, while Clinton took about two thirds of the African-American vote. For Clinton, that was a smaller share than in other contests. In Mississippi on Tuesday, for instance, she won nine out of 10 African American votes.

Clinton's projected 60-point margin of victory in Mississippi continued a string of wins in southern states, which began with South Carolina and continued through Super Tuesday last week. Mississippi has 36 Democratic delegates in play.

She and Sanders will also compete in Florida Ohio, Illinois and Missouri and North Carolina on March 15, as well as Northern Marianas Caucus on Saturday. Republicans have caucuses in the Northern Marianas and Washington, D.C. on Saturday, along with the five state primaries on March 15.

In the Republican race, Donald Trump won handily in Michigan, beating out Ohio Gov. John Kasich, who had been pushing for a strong finish in the state. Kasich came in second, followed by Texas Sen. Ted Cruz and Florida Sen. Marco Rubio, with 59 delegates up for grabs.

In Mississippi, Trump beat back a challenge from Cruz, who earned the endorsement of Gov. Phil Bryant and who expected to perform well with evangelical voters. Instead Trump beat Cruz among the evangelical population, exits polls show. Cruz, came in second, followed by Kasich and Rubio. Forty Republican delegates were in play.

In Michigan, voter turnout was also higher than in previous elections. The Detroit News reported that the Secretary of State's office projected that roughly 2 million voters, about 27 percent of the state's voters, turned out, making it a primary with one of the highest voter turnouts in recent history.